Sound amplifier



BES? AVML'BLE COPE Sept. 14 1926.

G. L. BAILEY SOUND AMPLIFIER 'Filed 'Dec. 27. 1924 @5M/wld? Y mme@ INV;i3. f MUORNEY Patented Sept. 14, 1926.

UNITED STATES PATENT OFFICE.

GABBOLD L. BAILEY, F NEWARK, NEW ERSEY.

SOUND AMPLIFIER.

Application led December 27, 1924. Serial No. 758,325.

This invention relates to devices for enhncing efr increasing the volumeof sound emanations. rendering audition more satisfactory, such devicesbeing variously termed sound amplifiers, loud speakers, resonators,

horns, etcetera..

One of the features of the present invention is in the provision of anamplifier made wholly of wood, because of its resonant properties,shaped in a novel and attractive form and so arranged internally thatniicrophonic sound waves are propagated ,i and eventually diffused withgreatly increased resonance duc to the sympathetic vibrations cf thestructure.

Another object is to provide an amplifier in which the sound waves asreceived from their source, are direct-ly through a channel ofconstantly increasing cross sectional area to a point Where they becomeseparated into equal parts, each passing through chambers havingrcsonating walls, to become combined into a perfectly synchronized unionprior to their eduction into the atmosphere with/ unusual sonorance andclarity.

These several aims and objects are accomplished by .the novelconstruction and arrangement of parts hereinafter described and shown inthe accompanying drawing,

forming a 'material part of this disclosure, and in Which:-

, Figure 1 is a perspective 'view of an einbodiment of theinvention,looking from its face.

Figure 2 is a front elevational'view of the ,apparatus with the face or'front wall removed.` f

Figure 3 isya vertical sectional'view taken on line 344,3 tif-Fig. 2.

Figure 4 is 'a transverse sectional view, taken in different planesers-indicated by the linea- 4 of Fig. 2.

lStated in general terms theapparatus consists of a hollow, drum-shapedbody, mounted on a base containing the microhone, to whichelectrical'connections lead rom the sound source.

Except for the metallic microphone socket and a gauze-like labricprevent entrance of'dust and insectsvvv through the sound issuingopenings at t-liev front, all parts of the device are .constructedentirely of wood, the casing or body walls and partitions beingpreferably made of hardwood veneer, shaped as shown and held in placeAby strong cement.

Referring more in detail to the drawing, the numeral 10 designates ingeneral a base. having a ilat rectangular lower surface, parallel frontand rear sides and ornamentally profiled' ends which slope symmetricallyto its concave upper surface 11.

A cylindrical band 12, of uniform Width and thickness is fixed on thecurved seat 11 and provided with an imperforate disc 13,

of corresponding diameter, at its back, a similar disc 14 being securedat the front, this front or cover disc having a generally ovoidalopening 15 in its lower portion, its bottom edge being substantiallyconcentric with the adjacent periphery of the disc, This opening is forthe emission of sound and is partially filled with ornamental fretworrlr16 of such fanciful design as may be preferred. 4

A lining7 not shown, of .any open meshed fabric may be applied to theinner side of the disc to prevent the entry of insects, dirt. and thelike, as will be readily understood.A

An open recess 17 is formed centrally in so the bottoni of the base 10to receive a microphone, indicated at 18 in broken lines, the samebeingr secured in a socket 19 extending from the recess 17 through thewall of the band 12 and an opening 20 in the rear 85 wall of the baseadmits the passage of conductors leading from the source of supply ofsound tothe microphone.

A tube 21, in the form of a reversed truncated pyramid, is arrangedcentrally within the band 12, its smaller, open end. enveloping theinner extending end of the. socket 19, and its larger, upper end,expanded to till the space between the discs 13 and'- 14, extends to adefinite spaced distance from the inner surface of the ring 12, at a'point' diametrically opposite the base, this distance beingapproximately' equal to onehalf the width .of the tube end.

A substantial] triangular abutment 22,100

having two nniormly curved sides blending into the band 12, to whichitis Secured esst Avait/iste com rg moonen transversely at'the top,presentsuits acute y. edge'drectly over the open en d of the tube 2l atits center.

*Accurately curved thin partitions Q3 exvili'tend between the discsifinnd il. these partitions joining the upper edge of 'the tube 2l toextend downwardly lslightlj,v below its center, essentially constitutinga circle. their lower ends being in contact with blocks '2l filling thespace between the walls of the tube 21 and respective front und reardiscs, but capable of vibrating and excluding 'Sie sound waves from thespaces enclosed by them, causing the sound wares to brauch oppcsitely.

A pair of opposed concm'ely curved lille? blocks 26, connected with thesides oif the vtubefujrl, extend outwardly along the rear [disc 13, fromthe ring elements 23 to the a band 12, to direct the sound wavesoutwdrdly through the opening l5, behind which j they are located, and acentral vertical strip 27 between the front of the tube and disc "/14completes the separation ot sound. 25 It is to be noted that the angularedge of the element 22 is arranged to bisect the tube 21, and its curvedportions are' so located with Areferences tothe lateral edges vof thetube, at their juncture with thepartitions 23, as to present e/erincreasing spaces for the sound waves over the halt' of the sectionalarea .of the larger end of the tube 21, the increment of passageincrease being more rapidly progressive between thewalls 23 and .l2 tothe outlet l5.

In operation, sound waves from a micro phone held in the socket 19passing upwardly through the tube 2l are deflected by l the triangularelement 22 to travel equally 40 but on opposite sides, between theelements 23 and bandl2, eventually to be directed outwardly, by theblocks 26, through the opening l5, and it will be noticed that the y,sound passages are constantly increasing in .45 sectional area from thesocliet 19 to the opening 15,*-while all corners or bends are socurved'or tilleted as to facilitate such travel. Aga-in reverting to theexclusive use of Wood, with .its known results and taking into.consideration the peculiar characteristics of construction described,it will be seen that a 'structure' has been'disclosv ,f fulfilling theseveral purposes mentioned. Although Ihave' described my improvementswith'considerable detail and with re spect to certain particular formsotA my invention, 'I do not desire to be limited to such details sincemany cl'ianges and modicutions may well bc inadewithoutdepart- #0 ingfrom the. spirit and scope of inyinvention ily-its broadest aspect. .y

Having thus described my invention, what I claim as new and desire tosecure by Letters' Patent, is

$5 LAfeound amplifier comprisinga base, a

capable of hollow'drum shaped casingseated on the base,' suidcusinghavingy openings on its iront wall, a socket in said' base receptive ofa microphone. a'hollowtruncated pyramid fixed in said drum with itssmaller end 79 open to said socket audits larger endA di- -rccteilupwardly in, direct couuuuuication with -the chamber in thecasing, meansin said casing to divert sound waves from the" pyrniuid in twosubstantially equal sections, partitions in the casing to producepassages of constantly increasing cross sectional area, und means at theends of said passages to expel the sound waves through the openings inthe face ot saidicasing. 8 2. A sound amplifier comprising a base, ahollow drum shaped casing seated on the ous-e, a socket in said basereceptive of a microphone', a tapered tube having its smaller terminalenclosing the end of Said socket and extending vertically towards the.periphery of the casing to a point substantially equal to half the widthof the larger end of the tube, a deector fixed on 'the interior,peripheral wall of the casing centrallyabove thev tube, a substantiallycircular partition enclosing the upper portion of saidtuber tween theside walls of 4the casing, and deilectors arrangedy on the rearwall ofsaid', casing between the circular qpartition'and '95l lower peripheralwall of the casing, the outer side wallo the casingy containingl open?ings for the emission of sound'. l A 3. A sound amplifier comprising abase', a.` hollow. cylinder seated on said baseand provided with fixedends at the rear and front,

`said front end'being perforate, means' in said base to contain amicrophone, a hollow cone disposed upright in said cylinder,l the Qsmaller end of the cone being in direct coin- N5 munication with 'themicrophone', meansv in l said cylinder for bisecting the conefat largerend, and means for conducting sound wavesl separately in each side ofthe cyl-inderto' deliver the saine outwardly through the per- `11o Aforstions in the frontend, alli-of said means being 'of constantlyincreasing cross sectional area.

4. A sound amplifier comprising abuse, a hollow cylinderseated onsaidbase and'pro- 115 vided with fixed ends at lthe lrear and front,said front end containing an" oval latticed opening in its lowerportion, said base 'containing a recess receptive-ot a microphone,"

means in said cylinderf to .conduct sound from the recess inthe base tothe upper portion of thecylinder,.means to divide the sound waves, andmeansto vcnduct the divided sound waves tothe opening lin the front wallof the cylinder, all ofthe sound' 125 conducting ineens progressivelyincreasing in cross sectional 'area and wholly composed of wood. f f

5. A.; sound vamplifier ,comprising a thin walled wooden drum shapedbody having@ 13o j ssemmsis copi Y aperforate front wall, a base onwhich the body rests, said base being provided with means to contain amicrophone, Wooden partitions forming channels in said body to rel ceivesound from a,microphone, means to divide the sound waves in theirpassage through the body, said partitions being subject to minutevibrations and arranged to and means to conduct the sound wav ontl0wardly through the perfornte front f of saidbody. This specificationsigned -and witnessed" this 10th day of December, 1924. A

GARROLD L. B AmEY.

constantly increase the of the'chyels,

all

